There are two Danish stamps I'll never own whose blank spaces bothered me for so long that I printed out copies of them on my home printer -- in their actual size -- but in black and white, not color. Then I cut them out and mounted them in the empty spaces. That's how deep and serious my addiction is! No one will ever mistake them for the real thing, but this points out how appealing filling a space with a copy can be for those addicted!
Paradigm pressure, I get it. But let me ask, why be a slave to the commercially printed album? They have spaces for all the values of a basic set, including the ones you can't afford, but the subvarieties go begging for space around and under the first mounted examples anyway. So why not kill both those birds by making your own pages to spec and using stockbooks/pages to create your page layouts? Then you can stick with real stamps and spare the next two generations the headache of telling good from bad. (That might be easy for you but out of reach for whoever inherits them.)
As for unaffordable Trans-Mississippi sets: consider doing them with card proofs. They are authentic archive material from the stamp producer, show the full designs and colors without cancellation, and cost but a fraction of the issued stamps. They fit standard mounts, and display well in albums for those who insist on that route.